HIV-1 Entry Inhibition by Small-Molecule CCR5 Antagonists: a Combined Molecular Modeling and Mutant Study Using a High-Throughput Assay

Total Page:16

File Type:pdf, Size:1020Kb

HIV-1 Entry Inhibition by Small-Molecule CCR5 Antagonists: a Combined Molecular Modeling and Mutant Study Using a High-Throughput Assay View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Virology 413 (2011) 231–243 Contents lists available at ScienceDirect Virology journal homepage: www.elsevier.com/locate/yviro HIV-1 entry inhibition by small-molecule CCR5 antagonists: A combined molecular modeling and mutant study using a high-throughput assay Jean Labrecque a,1, Markus Metz b,1, Gloria Lau a, Marilyn C. Darkes a, Rebecca S.Y. Wong a, David Bogucki b, Bryon Carpenter b, Gang Chen b, Tongshuang Li b, Susan Nan b, Dominique Schols c, Gary J. Bridger b, Simon P. Fricker a, Renato T. Skerlj b,⁎ a Department of Biology, AnorMED Inc. now Genzyme Corporation, 500 Kendall Street, Cambridge, MA 02142, USA b Department of Chemistry, AnorMED Inc. now Genzyme Corporation, 500 Kendall Street, Cambridge, MA 02142, USA c Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000, Leuven, Belgium article info abstract Article history: Based on the attrition rate of CCR5 small molecule antagonists in the clinic the discovery and development of Received 14 January 2011 next generation antagonists with an improved pharmacology and safety profile is necessary. Herein, we Returned to author for revision describe a combined molecular modeling, CCR5-mediated cell fusion, and receptor site-directed mutagenesis 13 February 2011 approach to study the molecular interactions of six structurally diverse compounds (aplaviroc, maraviroc, Accepted 18 February 2011 vicriviroc, TAK-779, SCH-C and a benzyloxycarbonyl-aminopiperidin-1-yl-butane derivative) with CCR5, a Available online 9 March 2011 coreceptor for CCR5-tropic HIV-1 strains. This is the first study using an antifusogenic assay, a model of the Keywords: interaction of the gp120 envelope protein with CCR5. This assay avoids the use of radioactivity and HIV HIV-1 infection assays, and can be used in a high throughput mode. The assay was validated by comparison with CCR5 other established CCR5 assays. Given the hydrophobic nature of the binding pocket several binding models Small molecule antagonists are suggested which could prove useful in the rational drug design of new lead compounds. Aplaviroc © 2011 Elsevier Inc. All rights reserved. Maraviroc Vicriviroc Mutagenesis Antifusogenic assay Homology modeling Binding site characterization The successful treatment of Acquired Immune Deficiency Syn- membrane, which ultimately results in viral load reduction when drome (AIDS) has been due to the introduction of Highly Active administered to humans (Allen et al., 2007). While CCR5 is used as a Antiretroviral therapy (HAART). Two classes of HIV drugs (e.g. coreceptor in the early stages of infection, the CXCR4 coreceptor using proteases and reverse transcriptases) are used in HAART to delay or virus is linked to significant disease progression leading to AIDS. In stop the progression of AIDS. However, because of side effects, contrast to in vitro results, other chemokine receptors have not been development of resistance, and challenges with patient compliance found to play a role as coreceptors for HIV infection under in vivo there is a continuing demand for new generations of viral inhibitors. conditions (Dragic, 2001; Kazmierki et al., 2005). Ideally, other classes of drugs interfering with viral replication by new The important role of these chemokine receptors in the HIV mechanisms could complement existing therapies (Barber, 2004; infection process was discovered in 1998, which led to a new Lusso, 2006; Markovic, 2006; Nadler and Phillips, 2005). classification of the three main HIV variants based on their chemokine One such new class, the entry inhibitors, prevents HIV entry into receptor selectivity: these classifications are CXCR4-tropic (X4), the target cell. In order for HIV to infect the host cell the gp120 viral CCR5-tropic (R5), and dual-tropic (R5/X4) (Berger et al., 1998). envelope protein must first bind to the CD4 receptor, and then to The development of small molecule antagonists of CCR5 to block HIV either one of two chemokine coreceptors, CCR5 or CXCR4, which are entry has been pursued by several pharmaceutical companies and G-protein coupled receptors, members of the seven-transmembrane multiple compounds have been evaluated in the clinic (Faetkenheuer domain family. Antagonists inhibiting or altering the interaction of et al., 2005; Klibanov, 2009; Kromdijk et al., 2010; Lalezari et al., 2005; HIV with these two coreceptors prevent viral fusion with the cell Lenz and Rockstroh, 2010; Palani and Tagat, 2006; Perry, 2010; Sayana and Khanlou, 2009; Shuermann et al., 2007; Strizki et al., 2005; Tilton et al., 2010; Wilkin et al., 2010). These small molecule antagonists have ⁎ Corresponding author. Fax: +1 781 672 5823. E-mail address: [email protected] (R.T. Skerlj). been found to bind within a binding pocket formed by the transmem- 1 Both authors contributed equally. brane helices (Billick et al., 2004; Dragic et al., 2000; Castonguay et al., 0042-6822/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.virol.2011.02.016 232 J. Labrecque et al. / Virology 413 (2011) 231–243 2003; Kondru et al., 2008; Maeda et al., 2006; Nishikawa et al., 2005; Pharmaceuticals (Maeda et al., 2004) and licensed by GlaxoSmithKline, Stupple et al., 2011; Seibert et al., 2006; Tsamis et al., 2003). The fact that was halted after patients in Phase II and III trials experienced liver toxicity these antagonists are small compared to HIV gp120 and that they bind in (Crabb, 2006). Thus, given the high attrition rate of compounds in the a cavity within the receptor makes it unlikely that a direct competition clinic increasing the understanding of how small molecules bind to CCR5 could occur between these inhibitors and gp120. Instead, mechanistic should help in developing structurally diverse antagonists with different studies have indicated that these antagonists act via an allosteric pharmacokinetic, pharmacodynamic and resistance profiles. mechanism, changing the conformation of the receptor and thus In this paper we provide a comprehensive description of the binding preventing the interaction of gp120 with CCR5 (Dragic et al., 2000; of the aforementioned antagonists to CCR5 using an antifusogenic assay, Watson et al., 2005). Though the details of this allosteric mechanism are which mimics the interaction of the viral envelope protein with CCR5. not fully understood, the concept of allosteric inhibition provides the After validating this assay with other in-house data (natural ligand opportunity to develop structurally diverse CCR5 antagonists with binding and HIV-1) and by comparing the effect of selected CCR5 amino different binding interactions potentially inducing different conforma- acid mutations on small molecule inhibition, an in-depth mutant study of tional changes of the receptor which are incapable of interacting with the potential allosteric binding site has been conducted. The conclusions the virus leading to different resistance profiles. To date only one CCR5 of this study are based primarily on our fusion assay data, with additional antagonist has successfully progressed through all the developmental literature information used to refine our small molecule binding hurdles. Pfizer's maraviroc was approved by the FDA for use in treatment hypotheses. This work is in line with other mechanistic studies aimed experienced patients in August 2007 (Perry, 2010; Sayana and Khanlou, at a better understanding of small molecule binding and inhibition of 2009) and following further clinical trials was approved for use in CCR5. Notably, use of the fusion assay provides a physiologically relevant treatment-naïve patients with CCR5-using virus in November 2009 technique for investigating drug/receptor interactions with the merits of (Kromdijk et al., 2010).Otheragentshavebeenlesssuccessful.Asthefirst not requiring active virus, and within a short assay time. Furthermore the of its class, TAK-779 was tested in clinical trials, but failed because of poor binding models provided by this assay, and reported in this paper, can pharmacological and/or toxicological properties as well as lack of oral provide valuable insights for rational drug design. bioavailability (Palani and Tagat, 2006). Schering-Plough has progressed two compounds (SCH-C and vicriviroc) into the clinic. However, Phase I Results studiesofSCH-CwerediscontinuedbecauseofprolongationoftheQT interval and Phase II studies involving treatment-naïve patients with Validation of a huCCR5/gp120 fusion assay as a technique for vicriviroc were stopped because of the increased likelihood of viral load interrogating compound/receptor interactions using receptor reboundcomparedtoagroupofpatientsusingstandardtherapy.In site-directed mutagenesis addition based on results of two Phase III trials of vicriviroc in treatment- experienced HIV-positive patients, vicriviroc did not meet its primary The amino acid sequence of CCR5 is shown as snake plot in Fig. 1 efficacy endpoint therefore, Merck will not submit an NDA for vicriviroc together with 34 single-site mutants to encompass all possibilities for (Merck, 2010). Development of aplaviroc, originally developed by Ono small molecule binding sites (Table 1). Fig. 1. Snake plot representation of CCR5; the mutated residues tested in the current study are highlighted and important residues are annotated. J. Labrecque et al. / Virology 413 (2011) 231–243 233 Table 1 inhibitor binding as reported in the literature: E283A, W86A, Y37A, Replicate analysis of amino acid mutations on fusion inhibition for the inhibitor SCH-C. Y108A, I198M and L33A which were shown to have a significant Mutation Mean IC50 SEM N contribution to inhibitor binding, and A29G and Y251F which had a minor contribution (Billick et al., 2004; Dragic et al., 2000; Castonguay Wild type 4.7 0.92 72 K26A 7.2 0.75 17 et al., 2003; Kondru et al., 2008; Maeda et al., 2006; Nishikawa et al., A29G 7.8 1.56 6 2005; Seibert et al., 2006; Stupple et al., 2011; Tsamis et al., 2003). The R31A 4.9 0.65 9 effects of these mutations on receptor/compound interaction on the L33A 131.3 8.93 41 small molecule antagonists shown in Fig.
Recommended publications
  • Download Article PDF/Slides
    Kan Lu, PharmD New Antiretrovirals for Based on a presentation at prn by Roy M. Gulick, md, mph the Treatment of HIV: Kan Lu, PharmD | Drug Development Fellow University of North Carolina School of Pharmacy Chapel Hill, North Carolina The View in 2006 Roy M. Gulick, md, mph Reprinted from The prn Notebook® | october 2006 | Dr. James F. Braun, Editor-in-Chief Director, Cornell Clinical Trials Unit | Associate Professor of Medicine, Meri D. Pozo, PhD, Managing Editor. Published in New York City by the Physicians’ Research Network, Inc.® Weill Medical College of Cornell University | New York, New York John Graham Brown, Executive Director. For further information and other articles available online, visit http://www.prn.org | All rights reserved. ©october 2006 substantial progress continues to be made in the arena of cokinetics and a long extracellular half-life of approximately 10 hours antiretroviral drug development. prn is again proud to present its annual (Zhu, 2003). During apricitabine’s development, a serious drug interac- review of the experimental agents to watch for in the coming months and tion with lamivudine (Epivir) was noted. Although the plasma years. This year’s review is based on a lecture by Dr. Roy M. Gulick, a long- concentrations of apricitabine were unaffected by coadministration of time friend of prn, and no stranger to the antiretroviral development lamivudine, the intracellular concentrations of apricitabine were reduced pipeline. by approximately sixfold. Additionally, the 50% inhibitory concentration To date, twenty-two antiretrovirals have been approved by the Food (ic50) of apricitabine against hiv with the M184V mutation was increased and Drug Administration (fda) for the treatment of hiv infection.
    [Show full text]
  • Review CCR5 Antagonists: Host-Targeted Antivirals for the Treatment of HIV Infection
    Antiviral Chemistry & Chemotherapy 16:339–354 Review CCR5 antagonists: host-targeted antivirals for the treatment of HIV infection Mike Westby* and Elna van der Ryst Pfizer Global R&D, Kent, UK *Corresponding author: Tel: +44 1304 649876; Fax: +44 1304 651819; E-mail: [email protected] The human chemokine receptors, CCR5 and suggest that these compounds have a long plasma CXCR4, are potential host targets for exogenous, half-life and/or prolonged CCR5 occupancy, which small-molecule antagonists for the inhibition of may explain the delay in viral rebound observed HIV-1 infection. HIV-1 strains can be categorised by following compound withdrawal in short-term co-receptor tropism – their ability to utilise CCR5 monotherapy studies. A switch from CCR5 to (CCR5-tropic), CXCR4 (CXCR4-tropic) or both (dual- CXCR4 tropism occurs spontaneously in approxi- tropic) as a co-receptor for entry into susceptible mately 50% of HIV-infected patients and has been cells. CCR5 may be the more suitable co-receptor associated with, but is not required for, disease target for small-molecule antagonists because a progression. The possibility of a co-receptor natural deletion in the CCR5 gene preventing its tropism switch occurring under selection pressure expression on the cell surface is not associated by CCR5 antagonists is discussed. The completion with any obvious phenotype, but can confer of ongoing Phase IIb/III studies of maraviroc, resistance to infection by CCR5-tropic strains – the aplaviroc and vicriviroc will provide further insight most frequently sexually-transmitted strains. into co-receptor tropism, HIV pathogenesis and The current leading CCR5 antagonists in clinical the suitability of CCR5 antagonists as a potent development include maraviroc (UK-427,857, new class of antivirals for the treatment of HIV Pfizer), aplaviroc (873140, GlaxoSmithKline) and infection.
    [Show full text]
  • Product Monograph for CELSENTRI
    PRODUCT MONOGRAPH PrCELSENTRI maraviroc Tablets 150 and 300 mg CCR5 antagonist ViiV Healthcare ULC 245, boulevard Armand-Frappier Laval, Quebec H7V 4A7 Date of Revision: July 05, 2019 Submission Control No: 226222 © 2019 ViiV Healthcare group of companies or its licensor. Trademarks are owned by or licensed to the ViiV Healthcare group of companies. Page 1 of 60 Table of Contents PART I: HEALTH PROFESSIONAL INFORMATION.........................................................3 SUMMARY PRODUCT INFORMATION ........................................................................3 INDICATIONS AND CLINICAL USE..............................................................................3 CONTRAINDICATIONS ...................................................................................................3 WARNINGS AND PRECAUTIONS..................................................................................4 ADVERSE REACTIONS....................................................................................................9 DRUG INTERACTIONS ..................................................................................................19 DOSAGE AND ADMINISTRATION..............................................................................28 OVERDOSAGE ................................................................................................................31 ACTION AND CLINICAL PHARMACOLOGY ............................................................31 STORAGE AND STABILITY..........................................................................................36
    [Show full text]
  • Microbicides 2008
    State of the Network Ian McGowan & Sharon Hillier Annual Meeting March 14th, 2016 HIV Infection in the US HIV Infection in US MSM HIV Infection in US Women Global HIV Infection HIV Incidence Rates in ASPIRE & RING Studies ASPIRE Study RING Study 10 8 6 4 2 HIV Incidence Rates (%) Rates Incidence HIV 0 <21 years > 25 years 18-21 years22-26 years27-45 years 21-25 years The PrEP Landscape in 2016 (1) • Oral PrEP – Optimization of Truvada delivery – Increasing availability – US, Canada, France, South Africa, Kenya, Israel – 2nd generation regimens being evaluated • Maraviroc combinations • Tenofovir alafenamide – New molecules • EFdA (Merck) The PrEP Landscape in 2016 (2) • Injectable PrEP – Rilpivirine & Cabotegravir • Intravaginal rings – Phase 3 • Dapivirine – Phase 1/2 • Tenofovir • Tenofovir disoproxil fumarate • Vicriviroc + MK 2048 • Dapivirine + Levonorgestrol The PrEP Landscape in 2016 (3) • Rectal microbicides – Phase 2 • Reduced glycerin tenofovir gel – Phase 1 • Maraviroc • Dapivirine • Griffithsin • MIV-150 / Carageenan / Zinc • Implantable PrEP MTN Highlights from the Past Year The MTN Portfolio 2015 / 2016 Studies in Ongoing development: Completed studies MTN-026 studies MTN-030 MTN-015 MTN-031 MTN-017 MTN-016 MTN-032 MTN-020 MTN-023 MTN-033 MTN-024 MTN-027 MTN-028 MTN-034 MTN-029 MTN-035 MTN-036 MTN-037 Intravaginal Ring Studies • Dapivirine • Vicriviroc / MK-2048 – MTN-020 – MTN-027 & MTN-028 – MTN-023 • Dapivirine 200 mg – MTN-025 (HOPE) IVR – MTN-029 – MTN-036 / IPM 047 – MTN-031 – MTN-034 • Dapivirine / Levonorgestrel – MTN-030 / IPM 041 Rectal Microbicide Studies • Tenofovir gel – MTN-017 • Dapivirine gel – MTN-026 – MTN-033 – MTN-035 CHARM-02 Study (Hiruy H et al.
    [Show full text]
  • Aplaviroc (APL, 873140)
    Hepatotoxicity observed in clinical trials of aplaviroc (APL, 873140) WG Nichols1, HM Steel1, TM Bonny1, SS Min1, L Curtis1, K Kabeya2, N Clumeck2 1 GlaxoSmithKline, Research Triangle Park, USA; 2 CHU-Saint-Pierre, Brussels, Belgium. Aplaviroc (APL, 873140, Ono 4128) O CH3 O HO • Specific CCR5 antagonist O N OH N NH • Potent HIV entry inhibitor O – mean 1.66 log10 decline at nadir in HIV-RNA after 10d monotherapy1 • Safety profile supported further study in humans 1 Lalezari J et al. AIDS 2005;19:1443–1448. Aplaviroc Phase 2b Program CCR100136 CCR102881 • 195 treatment-naïve • 147 treatment-naïve subjects randomized to subjects randomized to – APL 200mg BID / LPV/r – APL 600mg BID / Combivir – APL 400mg BID / LPV/r – APL 800mg BID / Combivir – APL 800mg QD / LPV/r – Combivir / efavirenz – LPV/r / Combivir – 2:2:1 randomisation – 2:2:2:1 randomization Sentinel case: Severe hepatitis • 39 year old HIV+ male – CD4 283 cells/mm3 – HBV/HCV negative – Normal AST/ALT/bilirubin • APL 800mg BID + COM • Day 59: developed severe hepatic cytolysis • Liver biopsy: – Chronic inflammatory infiltrate, mod intensity Liver biopsy (portal area) – Consistent with drug-induced hepatotoxicity CCR102881 Individual Patient LFT Plots ALP ALT AST BILT CK 70 60 50 40 30 APL RX 20 LFT Values (x ULN) 10 0 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 Study Day Review of Liver Enzyme Elevations in APL Phase IIb trials • 336 subjects received treatment – 282 subjects on APL – median duration of therapy: 13 wks • Central Lab database query to identify – any Grade
    [Show full text]
  • Managing Drug Interactions in the Treatment of HIV-Related Tuberculosis
    Managing Drug Interactions in the Treatment of HIV-Related Tuberculosis National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination Managing Drug Interactions in the Treatment of HIV-Related Tuberculosis Centers for Disease Control and Prevention Office of Infectious Diseases National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination June 2013 This document is accessible online at http://www.cdc.gov/tb/TB_HIV_Drugs/default.htm Suggested citation: CDC. Managing Drug Interactions in the Treatment of HIV-Related Tuberculosis [online]. 2013. Available from URL: http://www.cdc.gov/tb/TB_HIV_Drugs/default.htm Table of Contents Introduction 1 Methodology for Preparation of these Guidelines 2 The Role of Rifamycins in Tuberculosis Treatment 4 Managing Drug Interactions with Antivirals and Rifampin 5 Managing Drug Interactions with Antivirals and Rifabutin 9 Treatment of Latent TB Infection with Rifampin or Rifapentine 10 Treating Pregnant Women with Tuberculosis and HIV Co-infection 10 Treating Children with HIV-associated Tuberculosis 12 Co-treatment of Multidrug-resistant Tuberculosis and HIV 14 Limitations of these Guidelines 14 HIV-TB Drug Interaction Guideline Development Group 15 References 17 Table 1a. Recommendations for regimens for the concomitant treatment of tuberculosis and HIV infection in adults 21 Table 1b. Recommendations for regimens for the concomitant treatment of tuberculosis and HIV infection in children 22 Table 2a. Recommendations for co-administering antiretroviral drugs with RIFAMPIN in adults 23 Table 2b. Recommendations for co-administering antiretroviral drugs with RIFAMPIN in children 25 Table 3. Recommendations for co-administering antiretroviral drugs with RIFABUTIN in adults 26 ii Introduction Worldwide, tuberculosis is the most common serious opportunistic infection among people with HIV infection.
    [Show full text]
  • Semen-Mediated Enhancement of HIV-1 Infection Markedly Impairs the Antiviral Efficacy of Microbicides
    Institute of Molecular Virology Ulm University Medical Center Prof. Dr. Frank Kirchhoff Semen-mediated enhancement of HIV-1 infection markedly impairs the antiviral efficacy of microbicides Dissertation to obtain the Doctoral Degree of Human Biology (Dr. biol. hum.) at the Faculty of Medicine, University of Ulm presented by Onofrio Zirafi Heidenheim an der Brenz 2014 Present Dean: Prof. Dr. Thomas Wirth 1st reviewer: Prof. Dr. Jan Münch 2nd reviewer: Prof. Dr. Barbara Spellerberg Date of graduation: 5th December 2014 TABLE OF CONTENTS III TABLE OF CONTENTS ABBREVIATIONS ............................................................................................................. V 1 INTRODUCTION ....................................................................................................... 1 1.1 HIV LIFE CYCLE AND ANTIRETROVIRAL DRUGS .......................................................... 2 1.2 HIV TRANSMISSION ................................................................................................... 4 1.3 FACTORS IN SEMEN MODULATING HIV-1 INFECTION .................................................. 5 1.4 MECHANISM OF INFECTION ENHANCEMENT BY SEMINAL AMYLOIDS ........................... 6 1.5 COUNTERACTING AMYLOID-MEDIATED ENHANCEMENT OF HIV-1 INFECTION ............ 6 1.6 STRUCTURE-BASED PEPTIDE INHIBITORS OF AMYLOID FORMATION ............................. 7 1.7 MICROBICIDES ............................................................................................................ 8 1.8 SCIENTIFIC AIM ........................................................................................................
    [Show full text]
  • What Lessons Can We Learn from 20 Years of Chemokine T D Di ? Receptor
    What lessons can we learn from 20 years of chemokine receptdtor drug discovery? John G. Cumming, PhD 5th RSC / SCI symposium on GPCRs in Medicinal Chemistry 15th-17th September 2014, Actelion, Allschwil, Basel, Switzerland Outline Background: chemokines and their receptors Chemokine receptor drug discovery and development Emerging opportunities for chemokine drug discovery Conclusions and learning Chemokines and chemokine receptors CXC(α) • Chemokines (chemoattractant cytokines) are 70-120 aa proteins • 44 chemokines in 4 major families and 22 chemokine receptors in human genome • ‘Cell positioning system’ in the body • Many receptors bind multiple ligands • Many ligands bind multiple receptors Chemotaxis Human monocytes + CCL2 (red) Volpe et al. PLoS ONE 2012, 7(5), e37208 CCR2 antagonists inhibit chemotaxis and infiltration Vasculature CCL2 release Spinal or Peripheral Tissue Recruited monocyte Site of CCL2 release CCR2 antagonists inhibit chemotaxis and infiltration CCR2 antagonist Circulating monocyte CCL2 release CCL2 release from peripheral injury site or central PAF terminals Role of chemokine system in pathophysiology • Potential role in inflammatory and autoimmune diseases: Multiple sclerosis, Rheumatoid arthritis, COPD, allergic asthma, IBD, psoriasis - Expression levels of chemokines and receptors in relevant tissues and organs of patients and animal disease models - Mouse knockout ppyphenotype in disease models • Established role in HIV infection Katschke et al., 2001 Arthritis Rheum, 44, 1022 - CCR5 and CXCR4 act as HIV-1
    [Show full text]
  • A Novel Small Molecule CCR5 Inhibitor Active Against R5-Tropic HIV-1S
    www.nature.com/scientificreports OPEN Activity and structural analysis of GRL-117C: a novel small molecule CCR5 inhibitor active against R5- Received: 24 September 2018 Accepted: 1 March 2019 tropic HIV-1s Published: xx xx xxxx Hirotomo Nakata1,2, Kenji Maeda 3, Debananda Das 1, Simon B. Chang1, Kouki Matsuda3, Kalapala Venkateswara Rao4, Shigeyoshi Harada5, Kazuhisa Yoshimura5, Arun K. Ghosh4 & Hiroaki Mitsuya1,2,3 CCR5 is a member of the G-protein coupled receptor family that serves as an essential co-receptor for cellular entry of R5-tropic HIV-1, and is a validated target for therapeutics against HIV-1 infections. In the present study, we designed and synthesized a series of novel small CCR5 inhibitors and evaluated their antiviral activity. GRL-117C inhibited the replication of wild-type R5-HIV-1 with a sub-nanomolar IC50 value. These derivatives retained activity against vicriviroc-resistant HIV-1s, but did not show activity against maraviroc (MVC)-resistant HIV-1. Structural modeling indicated that the binding of compounds to CCR5 occurs in the hydrophobic cavity of CCR5 under the second extracellular loop, and amino acids critical for their binding were almost similar with those of MVC, which explains viral cross- resistance with MVC. On the other hand, one derivative, GRL-10018C, less potent against HIV-1, but more potent in inhibiting CC-chemokine binding, occupied the upper region of the binding cavity with its bis-THF moiety, presumably causing greater steric hindrance with CC-chemokines. Recent studies have shown additional unique features of certain CCR5 inhibitors such as immunomodulating properties and HIV-1 latency reversal properties, and thus, continuous eforts in developing new CCR5 inhibitors with unique binding profles is necessary.
    [Show full text]
  • Cytokines and Chemokines in SARS-Cov-2 Infections—Therapeutic Strategies Targeting Cytokine Storm
    biomolecules Review Cytokines and Chemokines in SARS-CoV-2 Infections—Therapeutic Strategies Targeting Cytokine Storm Alexandra Pum 1, Maria Ennemoser 1, Tiziana Adage 2 and Andreas J. Kungl 1,3,* 1 Institute Of Pharmaceutical Sciences, Karl-Franzens-University Graz, Schubertstrasse 1, 8010 Graz, Austria; [email protected] (A.P.); [email protected] (M.E.) 2 Brain Implant Therapeutics (BIT) Pharma, Leonhardstrasse 109, 8010 Graz, Austria; [email protected] 3 Antagonis Biotherapeutics GmbH, Strasserhofweg 77, 8045 Graz, Austria * Correspondence: [email protected] Abstract: The recently identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, the cause of coronavirus disease (COVID-19) and the associated ongoing pandemic, frequently leads to severe respiratory distress syndrome and pneumonia with fatal consequences. Although several factors of this infection and its consequences are not completely clear, the presence and involvement of specific chemokines is undoubtedly crucial for the development and progression of COVID-19. Cytokine storm and the often-resulting cytokine release syndrome (CRS) are patho- physiological hallmarks in COVID-19 infections related to its most severe and fatal cases. In this hyperinflammatory event, chemokines and other cytokines are highly upregulated and are therefore not fulfilling their beneficial function in the host response anymore but causing harmful effects. Here, we present the recent views on the involvement of chemokines and selected cytokines in COVID-19 and the therapeutics currently in clinical development targeting or interfering with them, discussing their potentials in the treatment of COVID-19 infections. Keywords: chemokines; SARS-CoV-2; COVID-19; coronavirus; cytokine storm Citation: Pum, A.; Ennemoser, M.; Adage, T.; Kungl, A.J.
    [Show full text]
  • HIV - Cancer ®
    Leronlimab (PRO 140) ® HIV - Cancer ® INVESTOR PRESENTATION January 2019 Professor Richard G. Pestell M.D., Ph.D., MB., B.S., F.A.C.P., F.R.A.C.P., F.A.A.A.S., M.B.A. Vice Chairman and Chief Medical Officer Nader Pourhassan Ph.D., President & CEO OTCQB: CYDY www.cytodyn.com Forward-Looking Statements This presentation contains certain forward-looking statements that involve risks, uncertainties and assumptions that are difficult to predict, including statements regarding leronlimab’s efficacy in certain cancer indications, the predictive value or benefit from the Company’s prostate cancer prognostic test, the Company’s clinical focus, and the Company’s current and proposed trials. Words and expressions reflecting optimism, satisfaction or disappointment with current prospects, as well as words such as “believes,” “hopes,” “intends,” “estimates,” “expects,” “projects,” “plans,” “anticipates” and variations thereof, or the use of future tense, identify forward-looking statements, but their absence does not mean that a statement is not forward-looking. The Company’s forward- looking statements are not guarantees of performance and actual results could differ materially from those contained in or expressed by such statements. In evaluating all such statements, the Company urges investors to specifically consider the various risk factors identified in the Company’s Form 10-K for the fiscal year ended May 31, 2018 in the section titled “Risk Factors” in Part I, Item 1A, and in our Form 10-Q for the quarterly period ended August 31, 2018 in the section titled “Risk Factors” in Part II, Item 1A, any of which could cause actual results to differ materially from those indicated by the Company’s forward-looking statements.
    [Show full text]
  • Recent Advances Targeting CCR5 for Cancer and Its Role in Immuno-Oncology Xuanmao Jiao1, Omar Nawab1,2,Tejal Patel2, Andrew V
    Published OnlineFirst July 10, 2019; DOI: 10.1158/0008-5472.CAN-19-1167 Cancer Review Research Recent Advances Targeting CCR5 for Cancer and Its Role in Immuno-Oncology Xuanmao Jiao1, Omar Nawab1,2,Tejal Patel2, Andrew V. Kossenkov3, Niels Halama4, Dirk Jaeger4,5, and Richard G. Pestell1,3 Abstract Experiments of nature have revealed the peculiar impor- reexpression augments resistance to DNA-damaging agents tance of the G-protein–coupled receptor, C-C chemokine and is sufficient to induce cancer metastasis and "stemness". receptor type 5 (CCR5), in human disease since ancient times. Recent studies suggest important cross-talk between CCR5 The resurgence of interest in heterotypic signals in the onset signaling and immune checkpoint function. Because CCR5 and progression of tumorigenesis has led to the current focus onTregsservesasthecoreceptorforhumanimmunodefi- on CCR5 as an exciting new therapeutic target for metastatic ciency virus (HIV) entry, CCR5-targeted therapeutics used in cancer with clinical trials now targeting breast and colon HIV, [small molecules (maraviroc and vicriviroc) and a cancer. The eutopic expression of CCR5 activates calcium humanized mAb (leronlimab)], are now being repositioned signaling and thereby augments regulatory T cell (Treg) dif- in clinical trials as cancer therapeutics. As CCR5 is expressed ferentiation and migration to sites of inflammation. The mis- on a broad array of tumors, the opportunity for therapeutic expression of CCR5 in epithelial cells, induced upon onco- repositioning and the rationale for combination therapy genic transformation, hijacks this migratory phenotype. CCR5 approaches are reviewed herein. C-C Chemokine Receptor Type 5 and Signal is preserved in immune cells (3) and cancer cells (4, 5).
    [Show full text]